Fire uses an inconsistent, outdated and noisy texture when compared to its campfire variants. The same thing can also be seen when comparing water to water bottles and lava to lava buckets.

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How to reproduce:
1. Get a campfire, soul campfire, flint and steel, soul soil, netherrack, lava bucket, water bucket, and water bottle from your inventory.
2. Dig 2 holes and place netherrack in one and soul soil in the other, then using flint and steel light both the netherrack and soul soil on fire, then place their campfire variants next to each-other.
3. Dig 2 holes again, this time putting water in one and lava in the other, then hold a lava bucket and water bottle in your hands.
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